It has been proposed to provide various forms of mowers, slashers, etc. in extendible arms off tractors and other like vehicles enabling an hydraulic operation of the arm through action of suitably connected rams. These types of equipment are commonly employed along roadsides, up the sloped surfaces of embankments and other areas where more standard forms of motorised mowers or slashers cannot go. In an orchard there is a need to mow beneath trees without fouling of the trees and an extension is required if a mower or slasher unit is to be extended beneath the trees. The usual unit is not adapted to this task and is unnecessarily complex for the task of mowing over what is essentially a flat surface.